1. Field of the Invention
This invention relates to feeding groups of articles. In one of its aspects, the invention relates to an improved system for filling containers with predetermined articles to preclude dumping incomplete groups of articles into the containers.
2. State of the Prior Art
Produce, such as carrots, are commonly sold in bags which contain a predetermined weight of the produce. For example, carrots are commonly sold in one pound plastic bags. The bagging of produce in one pound bags creates certain efficiencies in a supermarket but requires the wholesaler to package his products.
Weighing and bagging the produce is tedious, time consuming and costly for the wholesaler. Machines are presently available for bagging the produce when the produce can be fed in weighted quantities in a timed sequence to the bagging apparatus. An example of such a machine is the Formost Produce Bagger manufactured by Formost Packaging Machines, Inc., Seattle, Wash. However, weighing of the product by hand labor and feeding the same to a conveyor for the bagging operation is also tedious, time consuming and costly.
It has been proposed to use a weighing machine which could weigh the product until a desired weight is obtained and then dump the same into containers on a conveyor for feeding through the packaging machine. However, difficulty is encountered in keeping up with the packaging machine when a single weigh hopper is used. When plural weigh hoppers are used, difficulties are encountered in dropping more than one load of produce into a given container and in having some containers on the conveyor without any product.
In U.S. Pat. No. 2,698,692 to Jones, et al., there is disclosed a system for feeding articles to a plurality of retainers on a conveyor which is moved beneath a plurality of separate stacking means. Each of the stacking means collects a predetermined number of articles in a given stack and thereafter moves the stack of articles into one of two storage compartments. The articles are dropped from the storage compartment in synchronized movement with preselected containers on the conveyor. Positioning cams extending from the bottom of the conveyor which is beneath the storage compartments and actuate release of a stack of articles from a given storage compartment into a particular conveyor retainer.
U.S. Pat. No. 3,807,123 to Kihnke discloses a system for filling bags with a predetermined weight of articles, such as carrots, by feeding the articles seriatim to a weighing means and thereafter dumping the articles into the bag after a predetermined weight has been received in the weighing means. A gate extends across the path of articles fed to the weighing means as soon as a predetermined weight has been received therein.
In copending U.S. Patent Application Ser. No. 309,146, there is disclosed and claimed an article feeding apparatus wherein articles fed through a plurality of weighing hoppers are discharged into empty containers which pass therebeneath. In the disclosed embodiment, the hoppers dump in only preselected containers. In this system, occasionally hoppers will not be filled and the timing of the conveyor with the feed mechanism is such that the conveyor does not move at an optimum speed. Further, occasionally, a particular hopper will fill after the conveyor has stopped beneath the hopper and the hopper will thereafter discharge into the container. However, on occasion, sufficient time does not exist to complete the dump cycle which results in spilling of the articles and/or premature closing of the hoppers.
It has been suggested to put a photocell on the end hopper in the series to sense the presence of an empty container and to dump the hopper if the container is empty. However, if the photocell sees the article dumping in the hopper, it tends to cause the photocell operated switch to open and thereby prematurely terminate dumping of the hopper.